LONDON (Reuters Life!) - U.S. photographer David Zimmerman won top prize at the Sony World Photography Awards on Thursday for a series of landscape pictures of deserts in southwest America which he said were threatened by pollution.

Zimmerman was awarded $25,000 upon receiving the L'Iris D'Or Award at a ceremony in the southern French town of Cannes.

"My documentation of these remarkable deserts throughout Arizona, New Mexico, California and Nevada continues in an effort to influence preservation through public awareness, opinion and action," he said in a statement.

Bruce Davidson of the Honorary Judging Committee added that meaning and image coincided in the photographs.

"We live in an era of environmental awareness," he said.

"It is also an era of the image. Both can coexist to give us a sharper picture of the use and abuse of our deep oceans and beloved terra firma, which is far more at risk than we admit or know."

On his website www.davidzimmerman.com, Zimmerman said the U.S. southwest desert ecosystem was "extremely fragile, easily scarred and slowly healed.

"Its resources, including certain rare and endangered species of wildlife, plants, and fishes, and numerous archeological and historic sites, are seriously threatened by air pollution, inadequate Federal management authority and pressures of increased use, particularly recreational use."

Also announced at the awards ceremony was a new Prince's Rainforest Project Award backed by British heir to the throne Prince Charles, which went to Spain's Daniel Beltra.

Vincent Foong from Singapore was named the Sony World Photography Awards Amateur Photographer of the Year and veteran French photographer Marc Riboud won a lifetime achievement award which was announced in January.